The as-cast Mg - 5.25 wt.% Zn - 0.6 wt.% Ca alloy was extruded at different extrusion temperatures (270, 300, and 330 °C). The extrusion temperature has a significant effect on the grain size, texture and mechanical properties of the Mg-Zn-Ca alloy. Upon extrusion, the as-cast coarse grains underwent pronounced grain refinement and the second phases were broken up and formed stringers in the extrusion direction. With the decreasing extrusion temperature to 270 °C, the grain size of the alloy was refined to about 1.5 μm, basal texture became stronger, which led to the higher tensile strength and moderate elongation to failure.